1. Field of the Invention
This invention relates to the use of surfactants to solubilize water-insoluble solids in ready-to-drink beverages which are clear, stable and free of crystals, floc, sediment and any other phase separation phenomena. More particularly, the present invention relates to the formation of stable, clear beverage concentrates, beverage syrups and stable, clear finished beverages which contain water-insoluble solids which have been solubilized or micro-solubilized by an amount of surfactant that is substantially less than the amount of surfactant used in known dispersions and often less than the amount of the water-insoluble solids.
2. Related Background Art
A variety of water-insoluble solids are useful ingredients in beverages. Examples of such water-insoluble solids include, without limitation, flavor compounds, taste modifiers, nutrients and colors. While these water-insoluble solids may be dissolved in non-aqueous solvent systems to form solutions, when such solutions are added to a beverage syrup and subsequently included in an aqueous finished beverage, the water-insoluble solids precipitate, crystallize or oil-off due to the overall dilution of the non-aqueous solvent in which the solids were dissolved. In addition, in the absence of suitable surfactant(s), water-insoluble solids form large crystalline pieces or waxy or oily material floating on top in beverage concentrates and syrups, respectively. All of the above-noted phase separation phenomena, aside from the obvious negative aesthetic impact, prevent the effective delivery of flavor to a given beverage.
Hence, there exists a dilemma in the formulation of beverages containing such water-insoluble solids. Many approaches have been taken to address this problem. Most notably, methods such as encapsulation (U.S. Pat. No. 5,871,798), microemulsion (U.S. Pat. Nos. 4,835,002 and 6,251,441), emulsion (U.S. Pat. No. 4,946,701), etc., have been employed. In addition, it is known to simply add a solubilizer such as a surfactant to a beverage system in order to solubilize an otherwise insoluble component (U.S. Pat. Nos. 6,444,253, 6,048,566, 4,136,163, 4,230,688 and 4,296,093).
However, each of these approaches has associated disadvantages. For example, beverages containing encapsulations or emulsions are not optically, visually, clear, i.e., water-clear. What is more, microemulsions, while optically clear and stable, rely on large amounts of co-solvents and large amounts of surfactants; the latter are typically present in an amount that is at least five to ten times the amount of water-insoluble solids present. Such a high requirement for the amount of surfactant has potential negative impacts upon beverage quality and manufacturing efficiency. A finished beverage having such large amounts of surfactant may have off-tastes. In addition, such a beverage may not be amenable to typical beverage manufacturing processes, e.g., the dilution of concentrate to syrup to finished beverage (see above). Further, surfactants are also foaming agents; using a large amount of surfactant will generate foam during carbonated beverage manufacturing, will therefore have an impact on line speed and filling and will thereby complicate the manufacturing process. Finally, large amounts of surfactant may be beyond the regulatory limit in a given beverage market, thereby creating an additional hurdle to be overcome.
In short, there is a need for a method of formulating stable, clear beverages containing water-insoluble solids which does not suffer from the above-noted problems.